what if I made a little visual programming language for my synthesizer 🤔

[aeva@mastodon.gamedev.place]

I reworked the oscilloscope so that it now shows the range of samples in the time frame between refreshes. Here's a short video fo me playing around with inaudible low frequency oscillators. Also, I added a "scope" tile which you can use to snoop on specific tile outputs in place of the final output. I'm planing on eventually having it show the output over the regular background when connected so you don't have to switch modes to see it.

[aeva@mastodon.gamedev.place]

The scope line is sometimes a bit chonky because it's time synced, and recording causes it to lag a bit. It generally looks a bit better than in the video normally.

You can also make it worse by taking successive screenshots :3

[aeva@mastodon.gamedev.place]

mym tells me this is ghost house music #mollytime

[aeva@mastodon.gamedev.place]

and here's most of that patch

[aeva@mastodon.gamedev.place]

one of the things I think is neat about programming is the way fundamental design decisions of the programming languages you use inevitably express themselves in the software you write. for javasscript it's NaN poisoning bugs. for c++, it's "bonus data". unreal blueprints have excessive horizontal scrolling on a good day. blender geometry nodes evolve into beautiful deep sea creatures. as I've experimented with mollytime, I've noticed it has a wonderful tendency to summon friendly demons

[aeva@mastodon.gamedev.place]

I have all these big plans for using procgen to do wire management ( https://mastodon.gamedev.place/@aeva/114617952229916105 ) that I still intend on implementing eventually, but I'm finding their absence unexpectedly charming at the moment

[aeva@mastodon.gamedev.place]

anyone up for some doof and boop music #mollytime

[aeva@mastodon.gamedev.place]

a good test to see if your speakers can emit 55 hz or not

[aeva@mastodon.gamedev.place]

I whipped up a version of the doof-and-boop patch that automates the alternating connections with a pile of flip flops and I've been grooving out to it for the last two hours 😎

[aeva@mastodon.gamedev.place]

I tried doing a live jam for some friends tonight where I had the drum machine patch going along with a simple synth voice on top of that which I intended to drive with the midi touch screen keyboard I made back in January, but I quickly found that to be unplayable due to latency in the system. I'm not sure exactly where as I haven't attempted to measure yet.

[aeva@mastodon.gamedev.place]

I figure if I move the touch screen keyboard into the synth and cut out the trip through the midi subsystem that might make the situation a little better (again, depending on where the real problem is)

Anyways, it got me thinking, I think processing input events synchronously with rendering might be a mistake, and it would be better if I could process input events on the thread where I'm generating the audio.

[aeva@mastodon.gamedev.place]

I added an instruction called "boop" that implements a momentary switch, and built a small piano out of it, and also built a metronome in the patch. That is very playable, so the latency must have been something to do with having one program implement the midi controller and the other implement the synth. I think I had this same problem with timidity a while back, so maybe it's just linux not being designed for this sort of thing.

[aeva@mastodon.gamedev.place]

with one program being the midi controller and the synthesizer it's pretty playable, but sometimes touch events seem to get dropped or delayed. that is probably my fault though, there's a lot of quick and dirty python code in that path, though I'm not sure why it's only occasional hitches

[aeva@mastodon.gamedev.place]

k, I've got tracy partially hooked up to mollytime (my synthesizer), and with mollytime running stand-alone playing the drum machine patch (low-ish program complexity), the audio thread (which repeatedly evaluates the patch directly when buffering), the audio thread wakes up every 3 milliseconds, and the repeated patch invocations take about ~0.5 milliseconds to run, with most patch evals taking about 3 microseconds each.

[aeva@mastodon.gamedev.place]

almost a third of each patch invocation is asking the also if there's any new midi events despite there being no midi devices connected to mollytime, but that's a smidge under a microsecond of time wasted per eval, and it's not yet adding up enough for me to care so whatever

[aeva@mastodon.gamedev.place]

anyways, everything so far is pointing toward the problem being in the UI frontend I wrote, which is great, because that can be solved by simply writing better code probably unless the problem is like a pygame limitation or something

[aeva@mastodon.gamedev.place]

I switched pygame from initializing everything by default like they recommend to just initializing the two modules I actually need (display and font) and the audio thread time dropped, probably because now it's not contending with the unused pulse audio worker thread pygame spun up. The typical patch sample eval is about 1.5 microseconds now, and a full batch is now under a millisecond.

[aeva@mastodon.gamedev.place]

tracy is a good tool for profiling C++, but the python and C support feels completely unserious :/

[aeva@mastodon.gamedev.place]

making building with cmake a requirement to use the python bindings and then only providing vague instructions for how to do so is an odd choice.

[aeva@mastodon.gamedev.place]

using cmake is a bridge too far, so I figure I'll just mimic what the bindings do, but it turns out they're a bit over engineered as they're meant to adapt C++ RAII semantics to python decorators and I don't want to pay for the overhead for that when I could just have a begin and end function call to bind instead. that probably will have to be wrapping new and delete like they do though because there is no straight forward C call for this.